400 block what I need to know ?

MotorHead · 01-12-2003, 07:52 PM

I am going to look at a 400 block next weekend for a 406 buildup, all I know about it is that it is a 2 bolt and I asked the guy if it has ever been machined and he said he didn't think so. I have digital caliper and inside diameter measuring tool so I can get a pretty good idea of the bore.

Is there anything I should be looking or anything to stay away from ? The guy who had it is a drag racer and was going to build it up but is going with a 383 instead, I think one of the reasons is he is a little worried about overheating.

LD85 · 01-12-2003, 10:38 PM

When I bought mine I looked for the 509 casting number as it is from what I read the most sought after even if it is a 2-bolt main.

88-406 · 01-13-2003, 12:32 AM

Check around the deck surface very carefully for cracks. Look really close at the steam holes. They tend to crack on the deck between the steam holes and the bolt holes.

Good Luck

KM

SmokedTires · 01-15-2003, 08:06 AM

The 2 bolt main is suppose to be stronger than the 4 bolt. You should be able to drill the main for a 4 bolt main cap also.

The weakest block is said to be the 4 bolt with the 3 freeze plugs on each side. :cheers: